29 October 2026International edition
Vol. I · No.
29 October 2026
AI IN FASHION
DAILY
The daily briefing on AI in the fashion business
Where fashion meets artificial intelligence.
Jewellery and watches

Hum

Japan

Hum is a Tokyo fine jewellery brand founded by Tomohiro Sadakiyo and Yuka Iinuma. Its atelier hand-makes gold, platinum and diamond pieces with distinctive metal textures.

Facts
FoundersTomohiro Sadakiyo, Yuka Iinuma
BaseTokyo, near Harajuku
MaterialsGold, platinum, silver, diamonds
ProductionHandmade in Tokyo atelier
Websitehum-jewelry.com
Segment
Luxury
Categories
Jewellery
Sales channels
Own storesWholesale

What is Hum?

Hum is a Japanese fine jewellery brand with a boutique and workshop near Harajuku station in Tokyo. It was founded by jeweller Tomohiro Sadakiyo and designer Yuka Iinuma, who met at the Tokyo School of Jewelry. In 2019 the pair also opened a jewellery school to pass on their skills.

Products and positioning

Hum works from the material rather than from a fixed design, and its founders invent their own tools and techniques to create textures in metal. A team of artisans in the Tokyo atelier makes each piece by hand. Typical elements include:

  • Yellow gold combined with platinum or oxidised silver
  • Raw, rose-cut and antique-cut diamonds in mille-grain settings
  • Lace-inspired pieces, Art Deco style chains and signet rings
  • Rings set with ancient coins and granulation work

Its references are largely European, while the Japanese influence shows in the colours and textures of the metal and in a philosophy compared to a Japanese garden, which idealises nature with little artifice.

Distribution

Besides its Tokyo boutique, Hum is carried by specialist jewellery retailers abroad, including WHITEbIRD in Paris and Twist in the United States.

Why it matters

Hum belongs to the first generation of Japanese brands to use precious stones seriously, and has helped bring Japanese artisanal fine jewellery to international collectors.

Frequently asked questions

Who founded Hum jewellery?

Hum was founded by jeweller Tomohiro Sadakiyo and designer Yuka Iinuma, who met at the Tokyo School of Jewelry.

Where is Hum from?

Hum is a Tokyo brand with its boutique and workshop near Harajuku station.

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